A heterogeneous network can be configured to include various types of access nodes such as a macro access node, a micro access node, a pico access node, a femto access node, etc. In some heterogeneous networks, a wireless device at the edge of an access node coverage area can experience signal interference when frequencies are re-used by neighboring access nodes. Such interference may occur, for instance, at the edges of the access nodes due to overlapping with other access nodes. Such inter-cell interference (ICI) may degrade data transmission near coverage area edges, reducing data throughput and spectral efficiency to wireless devices near a coverage area edge. Existing methods to mitigate interference such as inter-cell interference coordination (ICIC) or scheduling schemes comprising almost blank subframes (ABS) require repeated communication between the cells, which increases overhead, or lose capacity due to muting resource blocks that could otherwise be used to carry traffic.
Overview
Exemplary embodiments described herein include systems, methods, and nodes for mitigating interference in heterogeneous networks. For instance, a method for mitigating interference in a wireless communication network comprises dividing a total number of resource blocks into a plurality of resource block sets, wherein one or more resource block sets from the plurality of resource block sets are allocated to each of a first access node and at least one additional access node that is proximate to the first access node, and rotating the allocation of said plurality of resource block sets for the first access node and said at least one additional access node. A system for mitigating interference in a wireless communication network comprises a processing node configured to determine one or more potential interference areas between a first access node and at least one additional access node, allocate a plurality of resource block sets across each of said first access node and at least one additional access node, each resource block set being assigned a resource block set number, and instruct each access node to rotate the allocation of the plurality of resource block sets starting from one or more of a different timestamp or a different resource block number. An access node in a wireless communication network comprises logic for mitigating interference in the wireless communication network by performing operations including determining a potential interference area between a sector of the access node and an overlapping sector of a neighboring access node, and rotating between resource blocks such that the sector of the access node that services the potential interference area uses a different resource block than the overlapping sector.